.\"
.\" SPDX-License-Identifier: ISC
.\"
.\" $OpenBSD: fido.4,v 1.4 2020/08/21 19:02:46 mglocker Exp $
.\"
.\" Copyright (c) 2019 Reyk Floeter <reyk@openbsd.org>
.\" Copyright (c) 2023 Vladimir Kondratyev <wulf@FreeBSD.org>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd August 21, 2023
.Dt U2F 4
.Os
.Sh NAME
.Nm u2f
.Nd FIDO/U2F USB security keys
.Sh SYNOPSIS
.Cd "device u2f"
.Pp
In
.Xr loader.conf 5 :
.Cd u2f_load="YES"
.Pp
In
.Xr sysctl.conf 5 :
.Cd hw.hid.u2f.debug
.Sh DESCRIPTION
The
.Nm
driver provides support for FIDO/U2F-compatible USB security keys.
They are Human Interface Devices (HID) which can be accessed via the
.Pa /dev/u2f/N
interface.
.Pp
The driver is compatible with the
.Xr read 2 ,
.Xr write 2 ,
and
.Xr ioctl 2
operations of the generic
.Xr uhid 4
device but only accepts the optional HID
.Xr ioctl 2
calls from u2f group users.
.Sh HARDWARE
The
.Nm
driver supports FIDO/U2F-compatible USB security keys.
.Sh SYSCTL VARIABLES
The following variables are available as both
.Xr sysctl 8
variables and
.Xr loader 8
tunables:
.Bl -tag -width indent
.It Va hw.hid.u2f.debug
Debug output level, where 0 is debugging disabled and larger values increase
debug message verbosity.
Default is 0.
.El
.Sh FILES
.Bl -tag -width /dev/u2f/* -compact
.It Pa /dev/u2f/*
.El
.Sh SEE ALSO
.Xr uhid 4 ,
.Xr usbhid 4 ,
.Xr usb 4
.Sh HISTORY
The
.Nm
driver first appeared in
.Fx 15.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Vladimir Kondratyev Aq Mt wulf@FreeBSD.org .
.Pp
This manual page was written by
.An Vladimir Kondratyev Aq Mt wulf@FreeBSD.org
based on the
.Ox
.Xr fido 4
manual page.
